Biomedical subjects

Aad van Der Lugt

Publications and source records attributed to Aad van Der Lugt.

3 recordsLinked to original sources

PubMed2005

Sixteen-detector row CT angiography of carotid arteries: comparison of different volumes of contrast material with and without a bolus chaser.

PURPOSE: To prospectively compare different volumes of intravenously administered contrast material with and without a bolus chaser at 16-detector row computed tomographic (CT) angiography of the carotid arteries. MATERIALS AND METHODS: Institutional Review Board approval and informed consent were obtained. Seventy-five consecutive patients (44 men, 31 women; mean age, 63 years; range, 22-85 years) were allocated to one of three protocols: group 1, 80 mL of contrast material; group 2, 80 mL of contrast material followed by 40 mL of saline; and group 3, 60 mL of contrast material followed by 40 mL of saline. Bolus tracking was used to synchronize contrast material injection with CT scanning. The attenuation in Hounsfield units was measured from the ascending aorta to the intracranial arteries at 1-second intervals. Differences were tested with the Student t test. RESULTS: The maximum attenuation was reached in the proximal internal carotid artery in all groups. The addition of a bolus chaser to 80-mL contrast material resulted in a higher mean attenuation (323 HU +/- 39 vs 351 HU +/- 60, P = .06), higher maximum attenuation (393 HU +/- 53 vs 425 HU +/- 76, P = .09), and higher minimum attenuation (240 HU +/- 34 vs 264 HU +/- 48, P < .05). Group 3 had lower mean, maximum, and minimum attenuation than did groups 1 and 2 (P < .001). CONCLUSION: The addition of a bolus chaser to 80 mL of contrast material results in a slightly higher attenuation. Decreasing the volume of contrast material from 80 to 60 mL results in a significantly lower attenuation.

Adult↗

PubMed2004

Sixteen-row multislice computed tomography: basic concepts, protocols, and enhanced clinical applications.

Since its introduction, spiral computed tomography (CT) technology underwent a continuous and fast technical and clinical development. In particular, spatial and temporal resolutions were constantly increased during the last decade. The main breakthrough for clinical application was the introduction of multislice technology, first with 2-row and 4-row equipment and more recently with 16-row scanners. A high-resolution sub-millimeter CT dataset can be acquired easily, although with an increased x-ray exposure for the patient. The high speed of the scan requires up-to-date and careful protocol optimization. Scanner technology and geometry affect image formation procedure and imaging protocols should be adapted accordingly. The technical foundations of spiral CT imaging and the main scan and reconstruction parameters are described in this article. Updated protocols and clinical examples of the latest applications are also discussed.

Concept Formation↗

PubMed2002

Evaluation of a dedicated dual phased-array surface coil using a black-blood FSE sequence for high resolution MRI of the carotid vessel wall.

PURPOSE: To investigate the ability of magnetic resonance imaging (MRI) to visualize the carotid vessel wall using a phased-array coil and a black-blood (BB) fast spin-echo (FSE) sequence. MATERIALS AND METHODS: The phased-array coil was compared with a three-inch coil. Images from volunteers were evaluated for artifacts, wall layers, and wall signal intensity. Signal intensity and homogeneity of atherosclerosis were assessed. Lumen diameter and vessel area were measured. RESULTS: Comparison between the phased-array coil and the three-inch coil showed a 100% increase in signal-to-noise ratio. BB-FSE imaging resulted in good delineation between blood and vessel wall. Most volunteers had a two-layered vessel wall with a hyperintense inner layer. MRI showed both homogeneous hyperintense and heterogeneous plaques, which consisted of a main hyperintense part with hypointense spots and/or intermediate regions. MRI lumen and area measurements were performed easily. CONCLUSION: High resolution MRI of carotid atherosclerosis is feasible with a phased-array coil and a BB-FSE sequence.

Adult↗